DLT DRIVE showing online allocation

VMS 7.3-2 having DLT drive issue.There was backup retoration was going on and it was giving restoration problem at one file and stuck there henc operation terminated by diconnection session. dismount command run to dismounty DLT, DLT tape removed after that it is showing online Allocation status. I have done mc syman> io autoconfigure /select=mke400for DLT device to load its driver. But issue not solved. I pushpull the DLT drive and check but not solved. Only system reboot is require for this to get DLT drive status to online ? Any othe option.